1. Field of the Invention
The present invention relates to an air conditioner. More specifically, the present invention relates to an air conditioner whose operation is controlled based on the comparison of the room temperature with the set temperature.
2. Description of the Prior Art
One example of an air conditioner capable of temperature operation is disclosed, for example, in the Japanese Utility Model application Laid-Open No. 99334/1981 laid open on Aug. 5, 1981. FIG. 9 shows this prior art. In reference to FIG. 9, a voltage divided by a room temperature sensor, namely, a thermistor TH and a temperature setter, namely, a variable resistor VR is applied to an input (-) of a comparator, namely, an operational amplifier OP. A reference voltage determined by a resistor R11 and a resistor R12 is applied to an input (+) of this operational amplifier OP. The operational amplifier OP compares these two inputs and gives the output thereof to a control circuit such as a microcomputer. The control circuit controls the operation of the air conditioner, that is, a compressor in response to an output from the comparator.
In the prior art as shown in FIG. 9, the temperature setting is performed by adjusting the variable resistor VR. However, users sometimes leave the setting intact always to a maximum (or minimum) value without adjusting such a temperature setter, namely, the variable resistor VR each time. In such a case, an excessive heating (or cooling) operation more than required is performed, and it is not preferable in the viewpoint of energy efficiency.